Spreading Depolarizations Have Prolonged Direct Current Shifts and Are Associated with Poor Outcome in Brain Trauma
Abstract
Cortical spreading depolarizations occur spontaneously after ischaemic, haemorrhagic and traumatic brain injury. Their effects vary spatially and temporally as graded phenomena, from infarction to complete recovery, and are reflected in the duration of depolarization measured by the negative direct current shift of electrocorticographic recordings. In the focal ischaemic penumbra, peri-infarct depolarizations have prolonged direct current shifts and cause progressive recruitment of the penumbra into the core infarct. In traumatic brain injury, the effects of spreading depolarizations are unknown, although prolonged events have not been observed in animal models. To determine whether detrimental penumbral-type depolarizations occur in human brain trauma, we analysed electrocorticographic recordings obtained by subdural electrode-strip monitoring during intensive care. Of 53 patients studied, 10 exhibited spreading depolarizations in an electrophysiologic penumbra (i.e. isoelectric cortex with no spontaneous activity). All 10 patients (100%) with isoelectric spreading depolarizations had poor outcomes, defined as death, vegetative state, or severe disability at 6 months. In contrast, poor outcomes were observed in 60% of patients (12/20) who had spreading depolarizations with depression of spontaneous activity and only 26% of patients (6/23) who had no depolarizations (x2, P less than 0.001). Spontaneous electrocorticographic activity and direct current shifts of depolarizations were further examined in nine patients. Direct current shift durations (n = 295) were distributed with a significant positive skew (range 0:51-16:19 min:s), evidencing a normally distributed group of short events and a sub-group of prolonged events. Prolonged direct current shifts were more commonly associated with isoelectric depolarizations (median 2 min 36 s), whereas shorter depolarizations occurred with depression of spontaneous activity (median 2 min 10 s; P < 0.001 ).
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 2011
- Accession Number
- ADA552236
Entities
People
- Ava M. Puccio
- Clemens Pahl
- David O. Okonkwo
- Jed A Hartings
- Jens Peter Dreier
- Johannes Woitzik
- Lori A. Shutter
- M. R. Bullock
- Martin Fabricius
- Tomas Watanabe
Organizations
- Naval Medical Research Center